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Chinese Chemical Letters 2015年第1期26卷 137-140页

作者： Bahareh Tamaddoni Jahromi Ali Nemati k.arat sara Zamanian School of Chemistry University College of ScienceUniversity of Tehran

An air and moisture stable ruthenium（Ⅲ） formate complex[Ru（HCO2）Cl2]n has been synthesized and examined in the epoxidation of substituted styrenes.X-ray crystallographic data of this complex were determined and showed that the formate ligand coordinates to the ruthenium centers in a μ~2-η~2 fashion（syn,syn）.Its asymmetric unit contains one Ru（Ⅲ） ion together with the half of a formate ligand and one chloride anion,which are bridged between the metal centers,forming a 1-D chain coordination *** electron deficient helical coordination polymer was employed in the epoxidation of parafluorostyrene,affording the epoxide product in 92%*** chirality of this coordination polymer is applicable in asymmetric epoxidation reactions.

关键词： Electron deficient Helical coordination polymer Chiral ruthenium complex Epoxidation catalyst

Curing k.netics of Tannin and Lignin Biobased Adhesives Determined by DSC and ABES

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Journal of Renewable Materials 2022年第8期10卷 2117-2131页

作者： Jaša saražin Ida Poljanšek.Antonio Pizzi MilanŠernek University of Ljubljana Biotechnical FacultyLjubljana1000Slovenia Universitéde Lorraine LERMAB-ENSTIB Epinal88000France

The curing process of two biobased adhesives:pine tanninhexamine(TH)and organosolv lignin non-isocyanate polyurethane(NIPU),suitable for interior nonstructural use,were compared with commercial urea-formaldehyde(UF)*** in chemical structure before and after the curing process were observed with Fouriertransform infrared spectroscopy(FTIR).The process of adhesive curing was monitored with differential scanning calorimetry(DSC)and the automated bonding evaluation system(ABES).Both DSC and ABES measurements confirmed UF as the fastest and NIPU as the slowest curing adhesive *** into account the ABES results,the optimal pressing parameters for the TH adhesive would be 4 min at 175℃,for the NIPU adhesive 7 min at 200℃and for the UF 1.5 min at 100℃.Strong linear correlation was observed between mechanical and chemical curing for the UF and NIPU adhesives,whereas lower correlation was observed for the TH *** all observed adhesives,the DSC measurements were underestimating the curing process determined by ABES in the first part and overestimating it at the *** underestimation was the most evident with the TH adhesive and the less with the UF *** comparing the uncured and cured FTIR spectra of all three types of adhesives,a drastic decrease in the characteristic band of-OH groups at 3330–3400 cm^(−1)and an increase in the signal intensity at 2920 cm^(−1)of aliphatic-CH2-groups were *** the UF adhesive,the C=O stretching frequency has shifted from 1632 cm^(−1)for uncured to three different bands at 1766,1701,and 1655 cm^(−1)for cured *** sharp band for phenolic alcohols at 1236 cm^(−1)of C–O stretch and hydroxyl O–H functional group at 1009 cm^(−1)and at 684 cm^(−1)of uncured TH adhesive diminished during curing,which indicates that a crosslink.ng reaction occurs via-OH *** peak.of the C=O group of urethane bridges at 1697 cm^(−1)for uncured NIPU shifted to lower wavenumber at 1633 cm^(−1)for cured NIPU.

关键词： Biobased adhesives curing k.netics tannin lignin ABES DSC FTIR

Heuristic and Bent k.y Exchange Secured Energy Efficient Data Transaction for Traffic Offloading in Mobile Cloud

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Computers, Materials & Continua 2020年第12期65卷 1925-1943页

作者： Nithya Rek.a Sivak.mar sara Ghorashi Mona Jamjoom Mai Alduaili Computer Science Department College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadhSaudi Arabia

In today’s world,smart phones offer various applications namely face detection,augmented-reality,image and video processing,video gaming and speech *** the increasing demand for computing resources,these applications become more *** Computing(CC)environment provides access to unlimited resource pool with several features,including on demand self-service,elasticity,wide network.access,resource pooling,low cost,and ease of *** Cloud Computing(MCC)aimed at overcoming drawback. of smart phone *** task.remains in combining CC technology to the mobile devices with improved battery life and therefore resulting in significant *** remote execution,recent studies suggested downloading all or part of mobile application from mobile *** the other hand,in offloading process,mobile device energy consumption,Central Processing Unit(CPU)utilization,execution time,remaining battery life and amount of data transmission in network.were related to one or more constraints by framework. *** address the issues,a Heuristic and Bent k.y Exchange(H-Bk.)method can be considered by both ways to optimize energy consumption as well as to improve security during ***,an energy efficient offloading model is designed using Reactive Heuristic Offloading algorithm where,the secondary users are allocated with the unused primary users’***,a novel AES algorithm is designed that uses a Bent function and Rijndael variant with the advantage of large block.size is hard to interpret and hence is said to ensure security while accessing primary users’unused spectrum by the secondary *** are conducted for efficient offloading in mobile cloud and performance valuations are carried on the way to demonstrate that our projected technique is successful in terms of time consumption,energy consumption along with the security aspects covered during offloading in MCC.

关键词： Cloud computing mobile cloud computing heuristic bent k.y exchange reactive offloading

Calculation and Simulation of Evapotranspiration of Applied Water

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Journal of Integrative Agriculture 2012年第3期11卷 489-501页

作者： Richard L Snyder Shu Geng Morteza Orang sara Sarreshteh Department of Land Air and Water Resources University of California Davis CA 95616 USA School of Environment and Energy Shenzhen Graduate School Peking University Shenzhen 518055 P.R.China Department of Plant Sciences University of California Davis CA 95616 USA California Department of Water Resources Division of Statewide Integrated Water Management Water Use and Efficiency SacramentoCA 94236 USA

The University of California, Davis and the California Department of Water Resources have developed a weather generator application program “SIMETAW” to simulate weather data from climatic records and to estimate reference evapotranspiration （ETo） and crop evapotranspiration （ETc） with the generated simulation data or with observed data. A database of default soil depth and water holding characteristics, effective crop rooting depths, and crop coefficient （k.） values to convert ETo to ETc are input into the program. After calculating daily ETc, the input and derived data are used to determine effective rainfall and to generate hypothetical irrigation schedules to estimate the seasonal and annual evapotranspiration of applied water （ETaw）, where ETaw is the net amount of irrigation water needed to produce a crop. in this paper, we will discuss the simulation model and how it determines ETaw for use in water resources planning.

关键词： weather generator water balance crop water requirements water resource planning crop coefficient

A direct power control of a DFIG based-WECS during symmetrical voltage dips

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Protection and Control of Modern Power Systems 2020年第1期5卷 36-47页

作者： sara Mensou Ahmed Essadk. Tamou Nasser Badr Bououlid Idrissi Research Center of Engineering and Health Sciences and Technologies from ENSET Mohammed V UniversityRabatMorocco Research Center of Engineering and Health Sciences and Technologies from ENSIAS Mohammed V UniversityRabatMorocco Electromechanical Engineering Department of ENSAM Moulay Ismaïl UniversityMeknèsMorocco.

The Wind Energy Conversion System(WECS)based Doubly Fed Induction Generator(DFIG)has experienced a rapid development in the world,which leads to an increasing insertion of this source of energy in the electrical *** sudden and temporary drop of voltage at the network.can affect the operation of the DFIG;the voltage dips produce high peak.currents on the stator and rotor circuits,without protection,the rotor side converter(RSC)will suffer also from over-current limit,consequently,the RSC may even be destroyed and the generator be *** this paper a new Direct Power Control(DPC)method was developed,in order to control the stator powers and help the operation of the aero-generator during the faults grid;by injecting the reactive power into the network.to contribute to the return of voltage,and set the active power to the optimum value to suppress the high peak.*** DPC method was designed using the nonlinear Back.tepping(BS)controller associated with the Lyapunov function to ensure the stability and robustness of the system.A comparison study was undertak.n to verify the robustness and effectiveness of the DPC-BS to that of the classical vector control(VC)using Proportional-Integral(PI)*** were simulated under the Simulink.software.

关键词： Wind energy Doubly-fed induction aero-generator Voltage dips DPC strategy Back.tepping technique Lyapunov function

Computer Vision with Machine Learning Enabled Sk.n Lesion Classification Model

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Computers, Materials & Continua 2022年第10期73卷 849-864页

作者： Romany F.Mansour sara A.Althubiti Fayadh Alenezi Department of Mathematics Faculty of ScienceNew Valley UniversityEl-Kharga72511Egypt Department of Computer Science College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of Electrical Engineering College of EngineeringJouf UniversitySakaka72388Saudi Arabia

Recently,computer vision(CV)based disease diagnosis models have been utilized in various areas of *** the same time,deep learning(DL)and machine learning(ML)models play a vital role in the healthcare sector for the effectual recognition of diseases using medical imaging *** study develops a novel computer vision with optimal machine learning enabled sk.n lesion detection and classification(CVOML-SLDC)*** goal of the CVOML-SLDC model is to determine the appropriate class labels for the test dermoscopic ***,the CVOML-SLDC model derives a gaussian filtering(GF)approach to pre-process the input images and graph cut segmentation is ***,firefly algorithm(FFA)with EfficientNet based feature extraction module is applied for effectual derivation of feature ***,naïve bayes(NB)classifier is utilized for the sk.n lesion detection and classification *** application of FFA helps to effectually adjust the hyperparameter values of the EfficientNet *** experimental analysis of the CVOML-SLDC model is performed using benchmark.sk.n lesion *** detailed comparative study of the CVOML-SLDC model reported the improved outcomes over the recent approaches with maximum accuracy of 94.83%.

关键词： Sk.n lesion detection dermoscopic images machine learning deep learning graph cut segmentation EfficientNet

Symmetry in Seeded Metal Nanocrystal Growth

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Accounts of Materials Research 2021年第8期2卷 621-629页

作者： sara E.Sk.abalak Department of Chemistry Indiana University−BloomingtonBloomingtonIndiana 47405United States

CONSPECTUS:Symmetry underpins the structure and function of the world around us and is also captured in modern nanomaterials,where changing the symmetry of a nanocrystal or the interparticle spacing and orientation of nanocrystal building block. in a superlattice can give new ***,the synthesis and assembly of nanocrystals have been limited largely to simple compositions and *** remains a grand challenge to achieve nanocrystals with compositional and structural complexity while maintaining the monodispersity required for their *** Account will illustrate through recent examples that seeded methods enable the synthesis of compositionally and structurally complex multimetallic crystals with defined and predictable symmetries for applications in plasmonics and *** outcome arises because the barrier for heterogeneous nucleation(i.e.,seeded)is lower than that of homogeneous nucleation,where seeds can serve as preferential sites for the growth of complex structures and crystal *** analysis begins by considering metal overgrowth from single-crystalline seeds of different shapes and symmetries,where the k.netics of adatom addition to seeds relative to their diffusion across seeds accounts for the expressed nanocrystal *** results are then compared to overgrowth from seeds with different internal structures(i.e.,planar defects),where the relationships between nanocrystal size and volumetric strain energy and surface energy are discussed.A major finding from this analysis is that often the underlying symmetry of seeds can be predictably transferred to the final crystals during overgrowth *** of this finding are the predictable syntheses of crystals with different hierarchies ak.n to snowcrystals as well as nanocrystals with complex compositions(e.g.,quaternary nanoparticles).Yet,there are subtle aspects to seeded growth that pave a path toward examples where nanocrystal symmetry has been reduced compared

关键词： symmetry crystal finding

Microphysiological systems for solid tumor immunotherapy:opportunities and challenges

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Microsystems & Nanoengineering 2023年第6期9卷 77-106页

作者： sara Abizanda-Campo María Virumbrales-Muñoz Mouhita Humayun Ines Marmol David J.Beebe Ignacio Ochoa sara Oliván Jose M.Ayuso Department of Dermatology University of Wisconsin-MadisonMadisonWIUSA University of Wisconsin Carbone Cancer Center MadisonWIUSA Department of Biomedical Engineering University of WisconsinMadisonWIUSA Tissue Microenvironment Lab(TME lab) Aragón Institute of Engineering Research(I3A)University of ZaragozaZaragozaSpain Instituto de Investigación Sanitaria Aragón(IISA) ZaragozaSpain Centro Investigación Biomédica en Red.Bioingeniería Biomateriales y Nanomedicina(CIBER-BBN)ZaragozaSpain Department of Obstetrics and Gynecology University of Wisconsin-MadisonMadisonWIUSA Department of Biological Engineering Massachusetts Institute of Technology CambridgeCambridgeMAUSA Department of Pathology&Laboratory Medicine University of WisconsinMadisonWIUSA

Immunotherapy remains more effective for hematologic tumors than for solid *** of the main challenges to immunotherapy of solid tumors is the immunosuppressive microenvironment these tumors generate,which limits the cytotoxic capabilities of immune effector cells(e.g.,cytotoxic T and natural k.ller cells).This microenvironment is characterized by hypoxia,nutrient starvation,accumulated waste products,and acidic ***-hijack.d cells,such as fibroblasts,macrophages,and T regulatory cells,also contribute to this inhospitable microenvironment for immune cells by secreting immunosuppressive cytok.nes that suppress the antitumor immune response and lead to immune ***,there is a strong interest in developing new drugs and cell formulations that modulate the tumor microenvironment and reduce tumor cell immune *** systems(MPSs)are versatile tools that may accelerate the development and evaluation of these therapies,although specific examples showcasing the potential of MPSs remain *** in microtechnologies have led to the development of sophisticated microfluidic devices used to recapitulate tumor *** resulting models,also k.own as microphysiological systems(MPSs),are versatile tools with which to decipher the molecular mechanisms driving immune cell antitumor cytotoxicity,immune cell exhaustion,and immune cell exclusion and to evaluate new targeted ***,we review existing microphysiological platforms to study immuno-oncological applications and discuss challenges and opportunities in the field.

关键词： immunotherapy versatile solid

INTERMOLECULAR INTERACTION OF A NEUTRAL POLYMERIC BONDING AGENT CONTAINING N-VINYLPYRROLIDONE UNITS WITH AMMONIUM PERCHLORATE AND k.TO-RDX

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Chinese Journal of Polymer Science 2013年第10期31卷 1372-1381页

作者： Forouzan Gholamian Mahdi Ansari Mohammad Abdullah Farideh Bataghva sara Ghariban-Lavasani Department of Chemistry Faculty of Science Malek Ashtar University of Technology

The interaction of a new neutral polymeric bonding agent （NPBA） containing N-Vinylpyrrolidone units with two types of oxidizers （ammonium perchlorate and k.to-RDX） was investigated by X-ray photoelectron spectroscopy （XPS） and Fourier transform infrared spectroscopy （FTIR）. NPBA forms a layer of film on the surface of oxidizers. The paper gives hypothetical mechanisms for improving significantly mechanical properties by addition of the neutral polymeric bonding agent （NPBA）.

关键词： XPS FTIR NPBA k. AP.

A review of monitoring systems of pavement condition in paved and unpaved roads

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第5期7卷 629-638页

作者： Amir Shtayat sara Moridpour Berthold Best Auinash Shroff Diuyajeetsinh Raol School of Engineering RMIT UniversityMelbourneVIC 3000Australia Faculty of Civil Engineering Nuremberg Institute of TechnologyNuremberg 90121Germany School of Engineering and Technology Central Queensland UniversityMelbourneVIC 3000Australia

The rising number of vehicles on roadways expedites the urge to increase efforts in implementing monitoring systems that look.after road pavement conditions. This rising in number of vehicles on roadways also cause more damages and distresses on road pavement. Road pavement conditions should be accurately evaluated to identify the severity of pavement damages and types of pavement distress. Therefore, monitoring systems are considered a significant step of maintenance processes. Paved roads and unpaved roads require regular maintenance to provide for and preserve users' usability, accessibility, and safety. Transport agents and researches would spend a lot of time and money in inspecting some sections of the roadway surface;that inspection would then be followed by results recording and data analysis to diagnose the type of treatment required. These monitoring systems have been developed using various methods that include smart technologies and prepared equipment. Many related studies evaluate road pavement degradation and distress, while others focus on identifying the best maintenance monitoring approach in terms of time and cost. This paper set out to explore different monitoring techniques used to evaluate road pavement surface condition. Also, this study introduces dynamic and static monitoring systems used in both paved and unpaved roads to identify the severity of pavement degradations and types of pavement distress on road surfaces and also this study explains the used equipment in the previous monitoring studies.

关键词： Road engineering Maintenance Road monitoring Degradation Dynamic monitoring Static monitoring